Initiating device for oil well tools



July 17, 1962 v. D. HANES INITIATING DEVICE FOR OIL WELL TOOLS 2Sheets-Sheet 1 Filed April 21, 1959 :9 INVENTOR. VAUGHAN DEAN HANESATTORNEY July 17, 1962 v, HANES 3,045,081

INITIATING DEVICE FOR OIL WELL TOOLS Filed April 21, 1959 2 Sheets-Sheet2 VAUGHAN DEAN HANES ATTORNEY United States Patent 3,045,081 INITIATINGDEVICE FOR OIL WELL TOOLS Vaughan Dean Hanes, West Covina, Califi,assignor to Aerojet-General Corporation, Azusa, Califi, a corporation ofOhio Filed Apr. 21, 1959, Ser. No. 807,928 8 Claims. (Cl. 200-61.53)

This invention relates to devices adapted to initiate operation of toolssuspended in a well and provided with self-contained operating meanswhich require to be started by an external agency. The invention isspecifically intendedfor initiating the operation of tools used in theoil well art.

Such wells require that a variety of operations be carried out such asacidizing, casing perforation, sealing 01f, or cementing. In suchoperations, actuation of the tool has to be effective at a particularpoint in the well bore, often at a depth of some thousands of feet.

In most cases the initiating device will be combined with a specializedtool, and since the particular construction of tool to be operated isimmaterial to the invention, the following description will refer to theinitiating device only, used with a propellant operated tool, by way ofexample.

The lowering of a tool into an oil well, particularly those wells ofconsiderable age or depth which are the type most frequently requiringspecial work, is often not a straight-forward matter. Such wells may notbe truly vertical, casings may have lengths which have bulged, or theremay be deposits on the inner surface of the casing or other obstructionstherein that interfere with lowering of cable carried tools.

It will exident that it is an advantage to use a wire line or cablesuspended tool capable of being jerked upward repeatedly in order toease or work the tool past obstructions in the well. I

In addition, even in wells that are clean and straight there may bemagnetic attraction between the well casing and the iron go-devil orcable which makes the use of a go-devil impratical, or there may betwists or kinks in the line which prevent the downward free fall of thegodevil.

For reasons above given, it is impracticable to trigger the firing orinitiating mechanism of a tool of the type described by the use of aconventional go-devil, which is a weight that is designed to be droppeddown the well guided by the tool cable to operate trigger mechanism ofthe tool.

It is also much cheaper to provide oil well tools with self-containedfiring means that may be operated by the well crew using the ordinarywell equipment since it is expensive to employ a service company tofurnish and operate the special electrical equipment required forelectrically operated tools controlled from the surface.

It is a particular object of the invention to provide an initiatingdevice for tools operated by the pressure of gas generated by a chargeof slow burning propellant or other source of potential energy,contained in the tool, the device being provided with means effective toinitiate operation only after several sharp upward movements of thedevice have been effected by the cable on which it is suspended.

It is another object to provide an initiating device for oil well toolsof the kind described, which is operated by an upward pull on the toolprovided that 'said upward movement is effected at a relatively rapidrate, whereas a slow raising of the suspending cable is effective tolift the device without causing its actuation.-

It is a further object of the invention to provide a simple andinexpensive device which may be used in most cases with the usualmeasuring line and reel used in the 3,045,081 Patented July 17, 1962 oilwell industry and can be operated by maintenance men or othersemi-skilled workers, thus avoiding the cost of special equipment andskilled crews.

It may be mentioned that a measuring line is a light line carrying aweight and running over a reel of known circumference, such as threefeet, furnished with a counter by which the length of line payed out isread. Such line and reel equipment is standard commercial equipment, thelines coming in various thicknesses according to the purpose for whichit is to be used. A line .187" in diameter designed to carry loads inexcess of 1250 lbs. is amply strong for use with the device of thisinvention.

Basically, the invention is a device to actuate a switch at a desireddepth within an oil well. A fluid damped weight is contained in aliquid-filled housing and is connected to a jerking means. Upon ajerking movement, the weight is moved downwardly displacing liquid andacts upon a cup-shaped member which reacts downwardly thereby actuatinga switch contact.

In the drawings:

FIG. 1 is a view in elevation showing the initiating device and welltool suspended therefrom being lowered into position in a Well.

FIG. 2 is a View similar to FIG. 1 showing the initiating device beingraised after having caused operation of the well tool by a rapid upwardpull on the cable.

FIG. 3 is a vertical central section through the initiating device inthe position shown in FIG. 1 but drawn on a larger scale.

FIG. 4 is a view similar to FIG. 3 but showing the position of the partsat the instant of initiation of the operating means in the toolsuspended from the device.

FIG. 5 is a schematic diagram of the electrical equipment and circuitsincorporated in the device in the inoperative position.

FIG. 6 is a schematic diagram of the electrical equipment and circuitsincorporated in the device in the operative position.

Referring now to FIG. 1, the numeral 1 indicates the well casing, theinitiating device 2 with attached tool 3 being suspended therein by aline 4 which runs over a sheave 7 and is operated by a winding drum 6.In FIG. 2, the initiating device is shown as having been operated andseparated from the tool 3 which is shown in set position in the wellcasing as indicated at 8, the numeral 9 indicating a gap showing thatafter firing no connection exists between the initiating device and thetool.

It is pointed out that the tool 3 is merely diagrammaticallyrepresented, the only requirement being that the tool should be providedwith self-contained operating means which require to be initiated intoaction by an outside agency. An example of such a tool is disclosed incopending application Serial No. 673,339, filed July 22, I957, assignedto the same assignee as in the present application.

As shown in FIG. 3, the initiating device 2 comprises an outer casinggenerally indicated at 10 having its upper end closed by a head13secured as indicated by threads 14 to the upper end of a short guidecasing 15 screwed into the top of a cylinder 16, as indicated at 17.

An operating weight member generally indicated at 11 is mounted in theupper portion of the casing 10, and self-contained electrical apparatusgenerally indicated at 12 is contained in the lower portion of thecasing. The components and circuit arrangement of the electricalapparatus which effects the transmission of current to initiateoperation of the tool 3 are more fully shown in FIGS. 5 and 6 and arelater described.

The lower end of the cylinder 16 is closed by a thick partition member18 having an axial bore 29 and screwed to the cylinder as indicated at19.

A case 2% is screwed as indicated at 21 to the partition member 18 andextends downwardly therefrom.

An end closure 22 is screwed to the lower end of the case 29 asindicated at 23, and is provided with a downwardly extending tubularextension, the bore 34 of which is closed by the liquid tight seal 34b.

It is to be understood that all components of the case are made up withwashers or rings between the parts so as to exclude oil well fluid fromthe interior of the case.

The casing llil is attached to line 4- by a stub 24 on the top surfaceof closure 13. An eye 25 is provided in the stub through which the line4 may be threaded and secured in any suitable manner.

The guide casing 15 is formed with a relatively thick base 26 providedwith an aXial bore 27 and drain holes 2%, the purpose of which will belater explained.

Base 26 provides a transverse partition toward the upper end of cylinder16.

Cylinder 16 is provided intermediate its length with an inwardlyprojecting peripheral flange 31, the inner surface of the cylinder abovethe flange being indicated at 3710, and below the flange at 31b.

The various elements of the self-contained electrical circuits may besecured in any suitable manner as by screws, to the walls 32, 33 of thecase 20.

The inertia operated motor arrangement ll comprises a cylindricalelongated weight 36 having a vertical guiderod screwed into the top ofthe weight as indicated at 37 and slidable in the bore 27 in the bottomof the casing 15.

The weight 36 is mounted on a helical spring 42 supported on the uppersurface 43 of inwardly projecting flange 3E. The lower portion of theweight is reduced in diameter as indicated at 38, the shoulder 41 thusformed providing a surface resting on the upper end of the spring 42.

A dashpot cylinder generally indicated at 4 is resiliently mounted belowthe weight 36, with the upper portion of the wall 39 of the cylindersurrounding the lower end of the reduced diameter portion 38 of theweight 36.

The cylinder 4i is guided for vertical movement by a vertical rod 44screwed into the relatively thick bottom of the cylinder as indicated at45 and working in the axial bore 29 in partition 18. An 0 ring packing39 is positioned around the rod 44 to prevent leakage of fluid throughthe bore 29. The rod 44 is provided with .a head 46 limiting its upwardmovement in partition 13 and the cylinder is yieldably held in its upperposition by a coil spring 47 mounted around the rod 44 between thebottom surface 49 of the cylinder 40 and upper surface 43 of thepartition 18. The pin 44 by its head 46 serves as an operating means forthe self-contained electrical initiation means as will later appear.When in its uppermost position 50 as shown in FIG. 3, head 46 is out ofcontact with the electrical means.

It will be noted that the sidewall 3? of cylinder 40 extends upwardlypast the flange 31 in its upper position as shown in FEG. 3 but is stillbetween the inner surface of the flange in the lowered position of thecylinder shown in FIG. 4, so that the flange 31 cannot causeinterference with the upper edge of the cylinder wall 39. The reduceddiameter portion 38 of the weight 36 projects into the upper end of thedashpot cylinder 40 in the raised position of the weight and projectsstill further into the cylinder 4% in the lowermost position of theweight as shown in FIG. The downward movement of the weight 36 islimited by head 51 of the weight guide rod 35 engaging against the uppersurface of base 26 of guide casing 15.

The upper chamber above the partition 18 in the casing lti is filledwith liquid, indicated at 52, to a level considerably above the upperedge of the wall 39- of the cylinder do to insure that the cylinder isalways filled with fluid below the reduced diameter portion 38 of weight36. The portion 33 of weight 36 is a loose fit in the cylinder 44 sothat the cylinder acts as a dashpot to the motion of the weight but adefinite downward force will be transmitted through the liquid againstthe bottom of the cylinder dd and cause downward movement of the pin 29depending on the speed of movement of the weight 36. To further controlor adjust the speed of flow of displaced liquid out of the cylinder 40,ports 53 may be provided in the wall of the cylinder adjacent the bottomthereof.

Guide rod 35 is a free fit in the bore 27 to ensure that no constraintis offered to free movement of the weight 36. Since in handling thedevice while outside the well, liquid will probably spill into the spaceabove guide member base 26, the drain passages 28 are provided to ensurethat the liquid will drain back into the casing 10 when the device isplaced in a perpendicular position in the well.

The schematic circuit shown in FIG. 5 includes a normally open singlepole single throw switch 54, operated by switch plunger 63a (shown inFIGS. 3 and 4), and a battery 55, one terminal of which is connected bylead 59 to one terminal of the switch, the other terminal of the switchbeing connected by lead 63 to ground. The other terminal of the batteryis connected by lead to one terminal of the solenoid 56s of a steppingswitch 56, the other terminal of the solenoid being connected by lead 64to ground.

Stepping switch 56 is shown as provided with twelve contacts, only thelast one 560, however, being connected to one terminal of a secondbattery 57 through lead 61. Stepping switch 56 is old in the art and isavailable from the Guardian Electric Company, Clare Relays, or theAutomatic Electric Company. The arm 56a of the stepping switch 56initially rests against one side of a stop 56s; and when stepped aroundto the live contact 56 rests against the opposite face of stop 56st. Thearm 56a is connected through lead 65 to ground.

The other terminal of battery 57 is connected through lead 62 to theelectrical igniter 58 positioned in the oil tool 3 for the gas producingmaterial, which may be a charge of slow burning propellant (not shown),then through lead 66 to ground. The igniter 58 may be of any type but isindicated as a coil of resistance wire which will be heated to red heator above when connected in circuit. It will be understood that theigniter is surrounded by gun powder or other pyrotechnic material, theignition of which will ignite the charge of slow burning propellant asis common practice.

In FIG. 6 the switch 54 is shown as closed and the stepper switch arm56a as resting on the 12th contact indicated at 560, thus completing acircuit from battery 57 through the electrical igniting element 58.

The arrangement of the reduced end 38 of the weight 3-6 loosely fittingin cylinder 40 which itself is a loose fit in the opening through theperipheral flange 31 and with liquid filling the lower portion ofcylinder 16, affords both a dashpot and lost motion arrangementpreventmg actuation of switch 54 by minor displacements of the weight11.

Operation In operation the initiating device 2 and the tool 3 suspendedtherefrom are lowered by the suspending measuring line 4- to the desireddepth as indicated in FIG. 1, the components of the device being in thepositions shown in FIG. 3 and the electrical circuit elements in theposition shown in FIG. 5.

A quick, short, upward pull on the line 4 will cause the outer case 10to be moved upward rapidly and the inertia of the resiliently mountedweight 11 will cause the reduced portion 33 of the weight 11 to entermore deeply into the bore of cylinder 40, displacing liquid therefromthrough ports 53 and surging between the walls of the cylinder andsurface of the piston 40. The pressure applied to the liquid in thecylinder 40 by the weight 11 will cause the cylinder 39 to movedownwardly, compressing spring 47 and causing guide pin 44 to closeswitch 54 which will result in moving the arm 56a of the stepper switch56 forward one step. The number of times the device requires to beupwardly jerked before the initiating circuit arranged therein isenergized will depend on the number of steps provided for, in theembodiment given by way of example the circuit would be completed on theeleventh sharp jerk when arm 56a will come to rest on live contact 56c.It is to be understood that each upward jerk of the line is followed bya lowering of the well tool to position.

If it is necessary to repeatedly jerk the device to clear obstacles inthe well bore or work it around them, the number of such movements willobviously be subtracted from the total number of sharp, upward movementsrequired to cause completion of the initiating circuit in the device. Ifit is desired for any reason to raise the device without operating it, aslow, upward pull is given by the line 4 which will result in the weight11 being carried upward with the device without changing its positionrelative thereto.

In the type of well tool operated by slow burning propellant, thecontinued build-up of pressure after opera tion of the tool is utiizedto shear the means 5 connecting the initiating device to the tool asshown in FIGS. 1 and 3.

It should be pointed out that tool contained operating means for oilwell tools, which means require to be initiated into operation by anoutside agency, may be of widely different types. For example, theinitiating device may be used to fire a squib effecting release ofchemicals into one another to generate the gas pressure operating thetool, or the firing of the squib may be eflective to disrupt a closureof a container and release a body of gas under high pressure in thecontainer into the tool.

The tool need not necessarily be freed from the initiating device afteropreation, as for instance, if a casing perforating gun is to beoperated, in which case the gun would be raised with the device afterfiring.

It is to be understood that while the initiating device has beendescribed with reference to a well tool, the device may be used toposition and set into operation various instruments used for takingreadings in wells, the term tool is therefore to be understood toinclude any instrumentalities used in Wells and provided withself-contained operating means requiring to be started or initiated intooperation by a separate device with which the instrumentality is more orless closely associated, and which is provided with means for generatingan electrical impulse transmitted to said instrumentality.

I claim:

1. A device for actuating a switch within a well comprising: aliquid-filled housing, means for displacing liquid in the housing, aresiliently biased means for containing liquid slidably disposed withinsaid housing positioned adjacent to said liquid displacing means suchthat the liquid displacing means may displace liquid in the liquidcontaining means, a rod fixedly attached to said liquid containing meansand extending externally through said liquid-filled housing, a switchmeans fixedly attached to said housing and in spaced relationship withsaid rod, and a means for operating said liquid displacing means wherebythe liquid is displaced within the liquid contain ing means therebytending to force the rod in contact with the said switch means.

2. A device for actuating a switch as defined in claim 1 and inaddition: a resilient means supporting the liquid displacing means in anupward position.

3. A device for actuating a switch as defined in claim 1 in which thesaid liquid displacing means is a weight, and resilient means coupledwith said weight to support it in an upward position.

4. A device for actuating a switch as defined in claim 1 in which thesaid liquid displacing means is a weight suspended in the saidliquid-filled housing, a resilient means supporting the said weight, anda jerking means fixedly attached to said weight.

5. A device for actuating a switch within a well comprising: aliquid-filled housing, a weight received by the said housing, apartition across the interior of said housing, a bolt fixedly attachedto the said weight extending through the said partition with its headportion in spaced relationship with the said partition, a resilientmeans supporting said weight and tending to hold the weight against thesaid partition, an open-top container slidably within said housing belowand in spaced relationship with the said weight, said container being ofsuch configuration to receive said weight, a resilient means supportingthe said container, a switch fixedly attached to the exterior of saidhousing and having a contact, a rod fixedly attached to said containerand in spaced relationship and axially aligned with the said switchcontact, and a cable attached to the said housing whereby a jerkingmotion of the cable causes a resultant downward movement in the weightdisplacing the liquid within the open-top container thereby causing therod to engage the switch contact.

6. A device for actuating a switch as defined in claim 5 and inaddition: an inwardly extending peripheral flange attached to theinterior of said housing and positioned in spaced relationship with thesaid container, and said resilient means supporting said weight incontact with said flange.

7. A device for actuating a switch as defined in claim 5 and in additionsaid container having a plurality of ports in its lower-most portionadjacent the said rod.

8. A device for actuating a switch within a well comprising: an uprightclosed substantially cylindrical casing having a first and a second end,liquid contained by said casing, a substantially cylindrical element inspaced relationship with the walls of said casing slidably suspendedwithin said casing from the first end, a resilient means contacting saidcasing and said cylindrical element urging said cylindrical elementagainst the first end of said cylindrical casing, a cup-shaped memberhaving an open end surrounding the cylindrical element in spacedrelationship with its sides and bottom with the closed end of thecupshaped member directed toward the second end of the said casing,resilient means contacting the casing second end and the said closed endof the cup-shaped member, means for slidably retaining the movement ofthe cupshaped member, a switch fixedly attached to the exterior of thesecond end of the casing and having a contact protruding therefrom, saidslidable retaining means positioned to be in spaced relationship withthe contact of said switch, and a jerking means coupled with the casingto cause the cylindrical element to be resiliently forced further withinthe cup-shaped member displacing the liquid therein causing the slidablyretaining means into engagement with the contact of the switch.

References Cited in the file of this patent UNITED STATES PATENTS450,626 Kerstein Apr. 21, 1891 2,577,210 Ruska Dec. 4, 1951 2,667,223Farris Jan. 26, 1954 2,854,539 Ruppel Sept. 30, 1958 2,950,908Rainsberger et al Aug. 30, 1960

